Supplementary Material for: Prevalence and factors associated with sarcopenia in community-dwelling older adults: a systematic review and meta-analysis

Background: Sarcopenia is a growing concern as a geriatric syndrome associated with various adverse health outcomes. Determining its prevalence and identifying risk factors are essential for effective prevention. Objective: This systematic review and meta-analysis aimed to estimate the prevalence of sarcopenia and identify the factors associated with sarcopenia in community-dwelling older adults. Methods: Guided by the PICo framework, we systematically searched six databases for relevant literature. Two reviewers independently assessed the quality of included studies. We performed a meta-analysis to estimate the prevalence of sarcopenia in overall older adults and subgroups. For risk factor analysis, pooled odds ratios (ORs) with 95% CIs were calculated, employing either random or fixed-effects models as appropriate. Results: A total of 52 eligible studies involving 70,202 older adults were included, among whom 7,488 were male and 9,054 were female. 40 studies were analyzed for both prevalence and related factors, while the remaining 12 were used for prevalence estimation only. The pooled analysis revealed a wide variation in the prevalence of sarcopenia among community-dwelling older adults, ranging from 5.2% to 50.0%, with an overall estimated prevalence of 18.8% (95% CI: 15.6%-22.4%) and substantial heterogeneity (I²=99.3%). Subgroup analyses showed that the highest rates were identified in studies using the EWGSOP 2018 definition (25.8%), Europe populations (23.4%), and using the anthropometric equations for muscle mass measurement (23.1%). Moreover, the factors significantly associated with sarcopenia in community-dwelling older adults were older age (OR = 3.3, 95% CI: 2.8–3.8), BMI (OR = 0.7, 95% CI: 0.6–0.9), malnutrition (OR = 3.4, 95% CI: 2.2–5.1), low physical activity (OR = 2.3, 95% CI: 1.8–2.8), current smoking (OR = 1.7, 95% CI: 1.3–2.2), and comorbidities such as osteoporosis (OR = 1.8, 95% CI: 1.3–2.4), osteoarthritis (OR = 1.4, 95% CI: 1.3–1.6), depression (OR = 3.0, 95% CI: 1.9–4.7), diabetes (OR = 2.8, 95% CI: 1.4–5.4), and cognitive impairment (OR = 2.5, 95% CI: 1.9–3.2). Conclusion: Our findings demonstrate a high prevalence of sarcopenia among community-dwelling older adults, with estimates significantly influenced by geographic region, diagnostic criteria and muscle mass measurement methods. The findings highlight heterogeneity due to non-standardized diagnostic methods and identify key risk factors including advanced age, low BMI, malnutrition, low physical activity, and comorbidities such as osteoporosis. These results underscore the need for unified diagnostic standards and early community-based interventions targeting modifiable risks.